If you suffer from a runny nose, sneezing, or red, watery, and itchy eyes, you likely only want one thing: relief. Thankfully, there are a host of over-the-counter (OTC) drugs that work well to treat seasonal allergies or hay fever. Benadryl is a popular option for many people.

Because you can purchase Benadryl at pharmacies and grocery stores without a prescription, you might think it’s safe to use in any situation. But Benadryl is a strong drug and it has a powerful effect on your body. It still comes with risks even though it’s available over the counter. For example, taking Benadryl with alcohol can cause severe effects.

Don’t take Benadryl with alcohol

Benadryl and alcohol are both central nervous system (CNS) depressants. Taking them together is dangerous because they can slow down your CNS too much. This can cause drowsiness, sedation, and trouble doing physical and mental tasks that require alertness.


Because Benadryl causes drowsiness, it may help you sleep better. In fact, the generic form of Benadryl, diphenhydramine, is approved as a sleep aid (brand-name Benadryl is not). Alcohol can also make you sleepy.

If you really want to get a good night’s sleep, though, don’t make the mistake of thinking a glass of wine and a dose of Benadryl will do the trick. The opposite is true. This misuse may actually make you dizzy and prevent you from sleeping through the night.

Benadryl may interact negatively with sleep aids and other medications. To be safe, you should only use Benadryl to treat your allergies.

Driving warning

You may have heard that you should not drive or use machinery if you take Benadryl (alone or with alcohol). This warning is because of the risks of CNS depression from the drug. In fact, the National Highway Traffic Safety Administration (NHTSA) suggests Benadryl may have a greater effect on a driver’s ability to stay alert than alcohol does. The NHTSA also agrees that alcohol can enhance the effects of Benadryl. You already know that drinking alcohol and driving is dangerous. Add Benadryl to the mix, and the behavior becomes even riskier.

In seniors

Drinking alcohol and taking Benadryl may be even riskier for seniors. This is because the combination inhibits your motor skills. Impaired motor ability combined with the dizziness and sedation from Benadryl can cause particular problems for seniors. For instance, the combination may increase the risk of falls in seniors.

Hidden sources of alcohol

Note that some medications may also contain alcohol. These include drugs such as laxatives and cough syrup. In fact, some medications are up to 10 percent alcohol. These drugs may interact with Benadryl. Read the labels on all the drugs you’re taking to lower your risk of accidental interactions or misuse.

If you’re taking more than one OTC or prescription drug or supplement, talk to your doctor or pharmacist. They can let you know if your other drugs contain alcohol and if it’s safe to take your other medications with Benadryl or not.

Benadryl basics

Benadryl is the brand-name version of an antihistamine called diphenhydramine. An antihistamine is a drug that interferes with the action of the compound histamine in your body.

Histamine is involved in your body’s immune response to allergens. It’s the reason you get a stuffy nose, itchy skin, and other reactions when you come in contact with something you’re allergic to. An antihistamine works by blocking your body’s response to these allergens. This can ease your allergy symptoms.

Benadryl does not affect your liver like alcohol does, but both drugs do work on your CNS. Therein lies the harm of mixing the two.

Learn more: All about antihistamines for allergies »

What to do

Don’t drink alcohol while you’re taking Benadryl. The combination comes with some serious risks. Benadryl is designed for short-term use, so it’s best simply to wait until you’re done taking Benadryl before you reach for a drink. You can ask your doctor or pharmacist how long to wait after you finish taking Benadryl before you have any alcohol. This includes beverages, mouthwashes, and other drugs that use alcohol as an ingredient.

If you drink a lot and find it difficult to hold off on drinking for a few days, consider reading up on resources and support.

Talk with your doctor

Benadryl is a strong drug. Make sure to read the label carefully and only use it to treat your allergies. Using Benadryl safely means not drinking alcohol while you take it. Combining the drug with alcohol can cause dangerous effects like extreme drowsiness and impaired motor skills and alertness. Benadryl and alcohol each make driving risky on their own. Using both together makes driving extremely dangerous. If you take Benadryl, ask your doctor how long you should wait after taking your dose before having a glass of alcohol.